What are testicles used for?

Explanation

The testicle is the male gonad which produces sperm and testosterone. Male vertebrates, humans includes, have two testicles, placed in the scrotum behind the penis. The testicles are placed outside the body because the production of semen works better at a lower temperature than the body's 37 degrees. The production of sperm and testosterone is controlled by hormones produced by thehypophysis